Currently, the assembly of electronic components involves the use of “pick-and-place” robots, which physically lift and move the components into a desired configuration. In some contexts, however, the use of such robots has become impossible or impractical. For example, the use of pick-and-place robots to assemble a large number of very small (e.g., mesoscopic or microscopic) components on large substrates has proven difficult, slow, and, as a consequence, very expensive. Such situations include, for example, the fabrication of large-area light emitting diode (LED) luminaires and displays, electronic skins and textiles, and photovoltaic devices.
Other approaches have attempted to solve some of these problems and include laser-assisted transfer, transfer printing, and directed self-assembly (DSA). DSA may employ the use of one or more forces, such as electrostatic force, magnetic force, or capillary force to assemble components in a parallel fashion without individually manipulating each component. DSA techniques may be carried out in air or a liquid.
Diamagnetic materials create an induced magnetic field oriented opposite to an applied magnetic field, resulting in repulsion of the diamagnetic material by the applied magnetic field. Diamagnetic materials may therefore be levitated by magnetic fields. Room temperature diamagnetic levitation has only been possible since the discovery of neodymium magnets and light, strongly diamagnetic materials, such as pyrolytic graphite (PG), sometimes referred to as pyrolytic carbon.